This invention relates generally to shopping carts and is particularly concerned with improved shopping cart strength and durability and ease of manufacture.
Traditional shopping carts have been made of bent wire stock for the basket side walls. If a child seat is provided it is attached at its lower end to the rear wall, and is pivoted away from the rear wall to use the seat. On nesting, the child seat is collapsed and the seat and rear wall are lifted by the front end of a cart nesting in from the rear. At the same time, the lower tray is also pivoted and is lifted by the lower end of the nesting cart. The various movable parts of such carts, to permit nesting, will tend to rattle as the cart travels, and also make nesting more difficult. Separating nested carts can also be a problem when there is deformation of the basket due to abuse or heavy loads. When the basket is deformed, the carts can no longer be nested.
U.S. Pat. No. 2,890,057 of Davis describes a conventional type of collapsing baby seat on a cart. Shopping carts are known which have different nesting arrangements, but these are subject to some other disadvantages. In my U.S. Pat. No. 6,126,181, a shopping cart with stepped, completely separate upper and lower baskets is described, in which the lower basket is offset forwardly from the upper basket, so that the lower basket of a rear cart can be nested under the upper basket of a forward cart for storage. The upper basket may include a child seat. However, the baskets are of reduced size and terminate short of the forward end of the cart. The base or lower tray is fixed and is stepped to permit nesting. In my U.S. Pat. No. 6,098,998, a shopping cart is described which has a child seat at the front end of the cart, and a pivoted rear wall for nesting. The lower tray or base is inclined downwardly from the rear to the front end of the cart to permit nesting without having to lift the lower tray, reducing moving parts. In my U.S. Pat. No. 7,168,711 a fixed baby seat is provided but the structural strength of the cart is compromised because there is no provision for a high strength frame for the basket top or bottom. Also in that patent the parts count is higher than in a conventional cart because of the use of a separate cantilever brace supporting the basket.